Research on test method for spandex fatigue of elastic warp knitted fabrics

In this paper,influences and significances of initial elongation and reciprocating stretching on spandex fatigue and runback of elastic warp knitted fabrics were tested and analyzed. And differences in spandex fatigue and runback of samples with initial elongation and without initial elongation test were analyzed,combined with results of trying on shorts. The results show that fatigue is serious as the increase of initial elongation percentage and the initial elongation percentage has significant influence on deformation rate and reversion rate of fabrics and fatigue grade of urethane elastic fibers; and fatigue and runback are serious as the increase of reciprocating stretching percentage,and the reciprocating stretching percentage has significant influence on deformation rate and reversion rate of fabrics and fatigue grade of urethane elastic fibers and runback number. Fatigue test results of initial elongation conform to actual wearing more,with the initial elongation percentage of 60%,and reciprocating stretching percentage less than 80%. The research results can provide a certain reference to fatigue test for elastic knitted fabrics.